The U.S. Justice Department said Tuesday it is appealing a court ruling that blocked President Barack Obama's plan to shield as many as five million people living in the country illegally from being deported.

The country's top law enforcement agency said it disagrees with a 2-to-1 appeals court decision Monday against an immigration policy executive order Obama issued nearly a year ago and will ask the U.S. Supreme Court to overturn the ruling.

Obama administration officials said they hope the country's top court will consider the case in a few months and issue a ruling by the end of its current term in June, just months before Obama's White House term expires in early 2017.

Obama's executive order is controversial in U.S. political circles, with conservative Republican lawmakers saying it is an overreach on his authority and an attempt to bypass Congress, which has been unable to reach agreement on changing U.S. immigration polices. The opponents call it amnesty for law-breaking, with millions of people entering the country without proper documentation.

Humane policy

Immigration advocates favor the Obama order, believing it to be a humane policy. They say it would ensure that many families who entered the country illegally but since have established their lives in the U.S. over several years would not have to fear they would be deported.

The Obama order is patterned after his 2012 program that postponed the deportation of hundreds of thousands of immigrants who entered the U.S. as children. Obama's executive order covers another 4.3 million people, allowing the undocumented parents of U.S. citizens to get work permits and stay in the country, provided they have lived in the United States for five years and not committed any crimes other than entering the country illegally.

FILE - Participants in an immigration rights rally walk under a giant American flag during a march through downtown Chicago.

Deportations

An estimated 11 million illegal immigrants live in the United States. The U.S. has been deporting about 300,000 to 400,000 of them a year for a variety of reasons, including if they have been convicted of a crime.

The case against the Obama order was brought by 26 states, all led by Republican governors. Texas Attorney General Ken Paxton, one of the officials seeking to block the Obama order, said the appellate court ruling "has secured an important victory to put a halt to the president's lawlessness."